Ddr Ram Question

[Penny]

This is a very stupid question...but i just bought a pentium 4 2.4gig with a gigabyte 8IE533 motherboard with pc2700 ddr ram...my questiuon is when i boot the PC up i show my ram speed is 266..sshouldnt pc2700 ram show up as 333...just wondering thanks

 

[Didou]

According to this page ( http://tw.giga-byte.com/products/8ie533.htm ), your board supports memory running at 100mhz ( 200mhz DDR or PC1600 ) & 133mhz ( 266mhz DDR or PC2100 ).

 

[Penny]

thanks for the reply....that sucks

 

[Phantasm66]

sorry to sound preachy, but its important to research these things before making a purchase....

 

[Penny]

i looked at other boards and stuff but when i went to a computer show they had this one so i got it...but oh well it works good enough

 

[Eric Legge]

The P4 would have to be running on a base FSB of 166MHz to be able to transfer data across the system bus at the same speed as the RAM running at 333MHz, because the processor can also only run at twice the rate of the base FSB.

The way you have it, the processor and the DDR RAM are transferring data over the system bus at 266MHz.

In short, there would be no system performance increase even if the board was able to run the RAM at 333MHz.

Eric,

http://www.legge40.freeserve.co.uk/BuyerBeware.htm

 

[Mictlantecuhtli]

Originally posted by Eric Legge
The P4 would have to be running on a base FSB of 166MHz to be able to transfer data across the system bus at the same speed as the RAM running at 333MHz, because the processor can also only run at twice the rate of the base FSB.

The way you have it, the processor and the DDR RAM are transferring data over the system bus at 266MHz.

In short, there would be no system performance increase even if the board was able to run the RAM at 333MHz.

I disagree. Take a look at how Intel 845E chipset works:

As you can see, the channels between CPU and Memory Controller Hub and between memory and MCH are separate ones. Most motherboards these days have an option to adjust FSB/memory speed ratio - I've set it to 3:4 in my motherboard. So now I have the CPU running @ 107 MHz and PC2100 memory runs @ 143 MHz. In my opinion, it does increase performance.

 

[SilentNoise]

It might be possible to run the memory at 166 if the BIOS has a 4:5 ratio for FSB/MEM.

Intel hadn't validated PC2700 ram when the I845E chipset was released, so board makers were given the possibility to allow memory at 166 but as an overclocking option.

 

[RustyZip]

How about overclocking the FSB to release the extra potential of the memory???

Is that an option??

 

[Penny]

alrighty well i have 1 more question..i bought pc-2700 ram for my p4 board(8ie533)i know it will only register at 266 speed...i also have a gigabyte 7vax board with the kt-400 chipset..i only have pc2100 in it...i was think of swtiching the ram sticks in these because the amd one will reconize the speed of the 2700 i think..(please correct me if i am wrong)and the p4 board will still work with the pc-2100 stick..will i notcice a lost of preformance on the p4 at all and will it increase the speed on the AMD that much thanks

 

[Mictlantecuhtli]

I don't think you'll notice any difference in your P4 system, but the AMD one might speed up somewhat - again, you probably won't notice it.

 

[Rick]

alrighty well i have 1 more question..i bought pc-2700 ram for my p4 board(8ie533)i know it will only register at 266 speed...i also have a gigabyte 7vax board with the kt-400 chipset..i only have pc2100 in it...i was think of swtiching the ram sticks in these because the amd one will reconize the speed of the 2700 i think..(please correct me if i am wrong)and the p4 board will still work with the pc-2100 stick..will i notcice a lost of preformance on the p4 at all and will it increase the speed on the AMD that much thanks

Keep in mind you will have to select your memory speed in the BIOS manually. I am not familiar with any boards that auto-detect memory speeds.

The performance different simply won't exist. It will in benchmarks I imagine, but for usage - I doubt that many people could be so discerning as to actually notice less memory bandwidth.

 

[eddy05]

I doubt you can feel the difference though. The difference is so slight that without actual benchmarks, you won't feel it, just like what Rick said.

Once after I updated my BIOS, I didn't notice any difference until I benchmark my system and found that the system became slower. That's when I check wCPUid and found out that my PC800 became PC600 after the BIOS update, and I revert to my old BIOS.

I feel as a home user you shouldn't really be concerned about slight performance increase if that meant messing around with hardware. Example, 1900+ is faster than 1800+, but I feel you shouldn't get 1900+ because the performace increase is unnoticeable unless you are willing to pay for it.

Tweaking your system is a good way to squeeze more performace.